Fold able blank box



Jan. 16, 1940, J. A; FARMER FOLDABLE BLANK BOX '5 Sheets-Sheet 1 Filed Oct. 23. 19s:

.az/Ww, 6 5%,

4 I J. A. FARMER 2,187,304

F OLDABLE BLANK BOX Filed Oct. 23, 1937 3 Sheets-Sheet 2 Jan. 16, 1940.

A. FARMER FOLDABLE BLANK BOX Filed Oct. 23, 19'? 3 Sheets-Sheet 3 Patented Jan. 16, 1940 UNITED STATES PATENT OFFICE- FOLDABLE BLANK BOX John A. Farmer, Lancaster, 2a., assiznor to A. H. Hoflman, lnc Landisvillc, Pa., a corporation of Pennsylvania This invention relates to folded blank boxes, and more particularly to boxes made of relatively heavy fibrous material such as corrugated board or fiber board, and commonly known as shipping cases. 7

Such boxes or containers are usually formed from a single blank of sheet material provided with the necessary creases or weakened fold lines dividing the blank into side panels and inner and n outer pairs of end flaps. In order to facilitate the proper folding in of these flaps, it has long been customary to cut away the material of the blank so as to form slots between the flaps, these slots extending substantially to the fold line. is This construction results in the formation of small holes at the corners after the flaps have been folded down, and for this reason it has heretol'ore been impossible to employ such containers for the shipment of loose fluent material. Where 29 such material is to be shipped, it has been necessary to either enclose it in bags or other packages, or to employ a liner in the shipping case, both of which methods are relatively expensive.

The general object of the present invention is to so construct a folded blank box or shipping case of this character that, when the flaps are folded down and cemented, the box will be completely and effectively sealed against leakage at any point, so that the box or shipping case may be used for packing loose fluent material in bulk, Without the necessity for any liner or auxiliary containers. In other words, the present invention contemplates the provision of a folded blank box or shipping case which shall be practically slit proof. To this end, a specific object of the invention is to provide an improved corner construction whereby, when the inner and outer flaps are folded down, the corner will be completely closed. a further object is to produce this result by means formed integral with the box blank and without the necessity for any separate corner pieces.

Another object of the invention is todevise i improved means for sealing the inner and outer end flaps, so as to completely avoid all cracksand crevices through. which fluent material might escape.

Other features and advantages of the invention will hereinafter appear as the description proseeds.

In order that the invention may be readily understood, reference is had to the accompanying drawings forming part of this specification and in which:

Fig. 1 is a developed view of one form of my improved blank;

Fig. 2 is a perspective view of the completed box or shipping case formed from such blank;

Fig. 3 is a fragmentary plan view on an en .5 larged scale showing one of the comer forming portions of the blank illustrated in Fig. 1;

Fig. 3 is a similar view showing a slightly modified arrangement;

Figs. 4, 5 and 6 are fragmentary perspective views illustrating this corner construction and showing successive steps in the method of folding the flaps;

Figs. 7 and 8 are fragmentary views similar to Fig. 3 but showing modified constructions; is

' Figs. 9 and 10 are fragmentary plan views showing the method of folding and assembling the parts of the corner construction illustrated in Fig. e;

Figs. 11 and 12 are views similar to Figs. l and 6, respectively, but showing the form of construction illustrated in Fig. 2

Fig. 13 is a perspective view of a conventional completed box of the type to which the invention relates, this view showing my improved method of sealing the end flaps;

Flgsls and 15 are sectional views on the lines l4i4 and l5-l5 respectively of Fig. 13 looking in the direction of the arrows; and

Figs. 16 and l! are fragmentary perspective views similar to Figs. 4 and 5 but showing the details of the taped corner illustrated in Fig. 2.

Referring to the drawings in detail, I have illustrated in Fig. l a blank consisting of four similar side panels a, "o, c, :2 having pairs of inner and outer top end flaps e, fig and h and similar bottom end flaps 2', la and l. The panels are separated from each other by corner fold lines l, from the end flaps by fold lines 2 and All the panels are shown as similar, and conse- A5 quently all of the naps areof the same size, each being. or" a width equal to half that of one o the panels. The panels, however, do not need to be square, but may be of any desired rectangularconfiguration. Preferably, however, all of 1: panels should be similar in order that the edge the flaps may lie on the same straight line 2*.

the form of blank, and may meet subst tially at the center when. fielded to form the box.

in forming the blans shown in Fig. 1 into 5% box such as illustrated in Fig. 2, the side edges of the panels a. and d are brought togethez and united by means if dhesive tape As above stated. is the common. practice to out the blank so to provide slots between $7.15:

III)

.- tirely, as shown in Fig. 3*.

side edges of the flaps, as shown at 6 in Fig. 1.

These slots, in the usual construction, extend,

By way of example, if the flaps are, say, sixinches wide, the bottom of the slots would terminate, say, one inch from the fold line. In Fig. 3, tFhe bottom of one of the slots 5 is indicated at I propose to tightly close or seal each corner of the box by means of a gusset or fillet, and in order to provide this, I make a cut from the bottom I of the slot substantially to the fold line 2. As shown in Fig. 3, this cut extends diagonally from one side of the bottom of the slot 6 toward the plane of the other side, the lower end of the cut 8 intersecting the fold line 2 at a point spaced laterally or offset from the corner fold line I between the adjacent panels. This method of cutting 'the blank produces a corner gusset or.

fillet 9 integral with one of the flaps such as 9, such fillet having an inclined edge and extending beyond the fold line I. There is also produced a triangular projection on the adjacent flap 1,

the bottom I of the slot appearing as a shoulder on the edge of the flap f, as clearly shown in Figs. 4, 5 and 6. This shoulder, however, serves no particular function.

It will be understood that the width of the slot 8, and consequently the degree of inclination of thecut line 8 'in Fig. 3 are, for the sake of clearness, shown somewhat exaggerated. In actual' practice, the shoulder I appearing in Figs.

4, 5 and 6 would be considerably smaller than shown in these views.

Moreover, since this shoulder performs no use ful purpose, it may conveniently be removed en- In this figure, it will be seen that a triangular section has been entirely removed from the bottom of the slot, thus leaving the fillet 9, having an inclined edge 8, as before. In this case, the side edge of the fiap f is left straight and smooth. Inasmuch as the slots 6 would be cut from the blank at a single stroke of a suitable cutting machine, the knife can be shaped to produce the form of cut shown in Fig. 3 without any additional expense.

As shown in Fig. 2, the flaps e and g are employed as the inner flaps, and the flaps f and h as the outer fiaps. By reference to Fig. 1, it will be understood that the out line 8 is reversely inclined at the oppositesides of each inner flap, such as g, so that the corner fillets 9 are produced at each side of each inner flap.

In Fig. 4, I have shown the appearance of a corner of the box after the ends of the blank have been united by means of the adhesive tape 4, but before the flaps have been folded down. The particular corner illustrated in Figs, 4, 5 and 6 is the corner diagonally opposite the adhesive tape 4 in Fig. 2.

. Referring again to Fig. 4, it will be particularly noted that the fillet 9 formed integral with the inner flap 9' extends somewhat beyond the line of the corner fold I. When, therefore, the inher fiap g is folded down, as shown in Fig. 5, this corner fillet 9 is bent over and compressed, and when the outer flap ,f is folded down on top of it, as shown in Fig. 6, this fillet 9 is wedged in between the two fiaps and further compressed and thus forms a complete and absolutely tight and sift proof corner. The invention is especially effective in connection with containers made of corrugated board, which is relatively soft and easily deformed.

In Figs. 16 and 17, I have illustrated the details of the corner carrying the adhesive tape 4. In the usual construction, this tape extends only to the fold line 2. In my improved construction, however, I extend it a considerable distance beyond this fold line, as indicated at 5, and I cut this extended end diagonally, as at 8, in substantially the same manner as the blank is cut at the other corners of the box, so as to provide a corner fillet 9. When the inner flap e is folded down, as shown in Fig. 17, this corner fillet portion of the tape is drawn tightly around the edge of the adjacent outer flap h, and then when this outer flap is also folded down, the corner is completely and tightly sealed by the tape. The inclination of the line 8 is exaggerated, as shown. In actual practice it would usually be more nearly straight.

It will be of course understood that what I have said about the upper corners of the box, and the flaps e, f, g and h, applies equally to the lower corners of the box and the flaps i, 7', k and Z, the inner flaps in each case having the corner fillets at each side extending beyond the adjacent corner fold line.

Instead of forming the cut on a diagonal line, as illustrated at 8 and above described, I may form this cut on a line 8' parallel with the sides of the slot, but offset laterally from the line of the corner fold I, as clearly shown in Fig, I. This results in forming a corner fillet 9' similar in function to the fillet 9, heretofore described, but having a parallel edge instead of an inclined edge. The appearance of this type. of corner construction, before the flaps are folded down, is clearly shown in Fig. 11, and it will be seen that the corner fillet 9' extends beyond the fold line I. When the inner panel 9 carrying this fillet is folded down, the fillet is compressed, as above described, and the corner is effectively sealed.

' Instead of the constructions shown in Figs. 1 to '7, 11 and 12, I may employ that shown in Figs. 8, 9 and 10. In this modification, I form a pair of cuts 8' and 8" each in line with the side edges of the adjacent flaps and g respectively These cuts form between them a tongue III, which extends on both sides of the corner fold line I. In assembling the box from a blank cut in this manner, the tongue I0 is first folded over toward the interior of the box, as shown in Fig. 9, and then the inner and outer flaps folded down in the vusual manner, as illustrated in Fig. 10. It will be seen that the tongue I0 fills and completely seals the opening which would otherwise be formed at the corner.

It will of course be understood that the extension 5 of the tape 4, shown in Fig, 2 may be cut as illustrated in Figs. 7 and 11, instead of as in Figs, 16 and 17, although, in a well made box, the crack between flaps at the taped corner is usually much narrower than the slot at the other corners.

In Figs. 13, 14 and 15, I have shown an improved method of sealing the joints between the flaps themselves so as to render the same sift proof. Although in these figures I have, for the sake of simplicity, shown only a conventional box, and have not attempted to illustrate my improved corner construction, it will, of course, be

understood that the box shown in these figures is intended to embody one of the improved corner constructions heretofore described.

It has long been the common practice, in clos- .murm

ing boxes or shipping cases of the type in question, to first fold in the inner flaps, then cover them with a coating of adhesive such as silicate of soda, and then press the outer flaps down upon this adhesive, so. as to securely hold the flaps together. With this method, it is apparent that a small hole or opening would be left at the intersection of the cracks between the two pairs of flaps.

In order to seal this opening, I employ a sealing strip of tough, flexible material, such as kraft paper. After bringing the inner flaps, such as e and 9, down into position, I apply such a sealing strip II by means of adhesive alon the crack between the meeting edges of these flapsj I then coat the outer surface of the inner flaps and sealing strip with adhesive, as indicated by the heavy line in Fig. 14, and press the outer flaps down upon the adhesive coated surface. In this way, the sealing strip is interposed between the pairs of inner and outer flaps. This is done, of course, at both the top and bottom of the box, as shown in the drawings.

When packing shipping cases of this character with loose granular or fluent material, it is difficult to support the inner top flaps with sufilcient firnmess to properly apply the sealing strip and press the outer flaps firmly against them. The material with which the case is filled and on which the inner flaps rest when folded down, is apt to yield, and permit the inner flaps to sink below the plane of the'top of the box, thus rendering proper sealing impossible.

To remedy this difliculty, I provide a bridge piece or support l2, as shown in Figs. 13 to 15. This may conveniently be formed of the same material as the box blank and is preferably U- shaped, comprising a horizontal portion and a pair of substantially parallel legs I2. These legs may be of such a lengthas to extend to and rest upon the bottom of the box, or, in some cases, shorter legs will sumce.

In using this device, I proceed as follows. The box is filled with fluent material and the bridge piece I! is then inserted by pressing the same down into the material, the legs I2" becoming embedded in the material and in some cases extending to the bottom of the box. In any event, the bridge piece is pressed down until its upper surface, which is positioned adjacent the center of the box, is substantially flush with the top edges of the box. As shown, the bridge piece It extends longitudinally of the meeting edges of the inner flaps.

After the bridge piece I! has been placed in position, it is coated with adhesive and the inner flaps then folded in and pressed down upon it. Then the sealing strip is applied, the whole coated -with adhesive and the outer flaps pressed down, as above described, the bridge piece sustainingthe inner flaps and holding them in substantially" horizontal position while the outer flaps are pressed down in close'contact with them. After the adhesive has set, the bridge piece is firmly united .to the inner flaps and forms a further reinforcement.

Owing to the complete and effective manner in which my improved shipping caseis sealed, it is desirable to provide some special means for opening the same and for dispensing the contents. This can conveniently be done by forming one of the side panels with a section adapted to be cut and folded back so as to provide a pourin which triangular marks I! and II are shown adjacent one upper corner of me side panel b, the marks I3 defining a line along which the section may be cut, and the mark it indicating a weakened line about which the triangular section may be folded back so as to provide an opening. Preferably the sides of the triangular opening thus formed are substantially parallel with the side and top edges of the box and are as close as practicable to the corner; g

In order to call the purchasers attention to this dispensing opening and to aid him in properlymanipulating thesame, I preferably enclose the above mentioned triangular section within an outline [5 representing the head of an arrow, the shaft l6 of the arrow extending diagonally across the panel and having printed thereon in structions or directions for opening the box. This dispensing feature is not claimed herein but is reserved to form the subject matter of a separate application.

What I claim is:

1. A blank for folded blank boxes comprising side panels andinner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, and also having slots between the flaps, the inner ends of said slots terminating short of the fold line between the flaps and panels, and said blank having a cut through the entire thickness thereof extending from the inner end of each slot substantially to the said last mentioned fold line. the inner end of said out being spaced laterally from the adjacent fold line between panels, in a direc'-. tion away from the inner flap, thus forming a corner fillet integral with the inner flap and wholly free from the outer flap.

2. A blank for folded blank boxescomprising side panels and inner and outer end flaps, said blank having .fold lines between the panels and between each flap and its adjacent panel, and also having slots between the flaps, the inner ends of said slots terminating short of the fold line between the flaps and panels, and said blank having a pair of spaced cuts passing entirely through the thickness thereof extending from the inner end of each slot substantially to the said last mentioned fold line and forming a tongue between them.

3. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, and

also having slots between the flaps, the inner ends of said slots terminating short of the fold line between the flaps and panels, and said blank having a-pair of-spaced cuts passing entirely through the thickness thereof extending from' the inner end of each slot substantially to the said last mentioned fold line and forming a tongue between them, said cuts being substantially parallel and each being oifset from the adjacent fold line between panels.

4. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, the

' side edges of each inner flap having adjacent the fold line between itself and the panels, corner fillets of the same thickness as the flap formed integral with theflap and entirely free at one edge throughout the length thereof and through their whole thickness, said corner fillets rendering the flap, adjacent said fold line, wider than the main body of the flap.

5. A blank for folded blank boxes comprising 7.

side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, the side edges of each inner flap having adjacent the fold line between itself and the Panels, corner fillets formed integral with the flap, and entirely free at one edge, and the free edge of each of said fillets being shaped to be forced into close contact with the inside of the outer flap with a wedging action, when the inner flap is folded over.

6. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, and also having slots between the flaps, the inner ends of said slots terminating short of the fold line between the flaps and panels, the side edges of each inner flap having integral corner fillets entirely free at one edge projecting therefrom and extending from such side edge at the inner ends of said slots .beyond the fold line between panels substantially to the fold line between the flaps and panels, whereby, when said panels are folded to box form, said fillets are bent around the corners of the box.

7. A folded blank box having side panels and inner and outer end flaps, the adjacent side edges of two of the panels being united at the corner byadhesive tape, said tape extending beyond the fold line between panels and flaps and secured to the two adjacent flaps, said tape, in the region between said flaps, being cut from its end substantially to said fold'line, the inner end of such out being displaced laterally of the corner line, whereby the portion of the tape adhering to the inner flap forms afillet to seal the corner fold.

8. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, each inner flap having, adjacent the fold line between itself and the adjoining panel, free inclined side edges, and the flap at this point being wider than at other points, whereby, when the inner flap is folded inward, said free inclined side edges adjacent the fold are wedged between the outer flaps and into close contact with the inside surface thereof.

9. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each' flap and its adjacent panel, the side edges of each inner flap having, adjacent the fold line between itself and the adjoining panel, later ally extending fillet portions having free edges, said portions rendering the, flap of maximum width at this point, whereby; when the flap is folded inward, the free edges of said laterally extending portions are forced between and into close contact with the inside surface of the outer flaps.

10. A blank for folded blank boxes comprising side panels and inner and outer end flaps, said blank having fold lines between the panels and between each flap and its adjacent panel, the side edges of each inner flap having, adjacent the fold line between itself and the adjoining panel, laterally projecting fillet portions having freeedges, each fillet portion extending from the edge of the inner flap at a point out of line with the fold line between panels to at least as far as a point in line therewith.

JOHN A. FARMER. 

